[release]A man was seriously injured by sewage gas explosion on Sunday in central China's Hunan Province. But the injured man himself was the one to blame to cause the accident.

Scripts of a video recorded by surveillance cameras in the residential area Mr. Cai, the injured man lives, shows that he was setting off firecrackers in the neighborhood. The explosion took place when he threw a firecracker into the sewer through a hole on the manhole cover, with the two kids looking from nearby. In a split of a second, Mr. Cai was blown by two meters away from where he stood.

Video scripts from another surveillance camera shows that the manhole cover weighing some 20 kilograms was blown up to as high as the third floor of a nearby building. The victim's coat was torn into pieces by the blast.

The kids, his son and nephew, were lucky enough to escape unhurt.

Residents in the community rushed Mr. Cai to a hospital.

A doctor in the hospital said that the victim suffered from facial burns and inhalation injury. He remained in critical conditions.

The explosion was believed to be caused by high explosive biogas accumulated inside the sewer.[/release]